question 6 of 29\nbetween a 2.0 m aq. nano₃ and 1.5 m aq. alcl₃ solution:\nwhich would have a lower freezing…

question 6 of 29\nbetween a 2.0 m aq. nano₃ and 1.5 m aq. alcl₃ solution:\nwhich would have a lower freezing point?\no 2.0 m nano₃\no 1.5 m alcl₃\no the freezing point is the same for both solutions.\nwhich would have a higher boiling point?\no 2.0 m nano₃\no 1.5 m alcl₃\no the boiling point is the same for both solutions.
Answer
Explanation:
Step1: Determine van't Hoff factor (i) for each compound
$NaNO_3$ dissociates into $Na^+$ and $NO_3^-$, so $i = 2$. $AlCl_3$ dissociates into $Al^{3 + }$ and $3Cl^-$, so $i=4$.
Step2: Calculate the effective concentration for freezing - point depression and boiling - point elevation
For $NaNO_3$, effective concentration $= 2.0\ M\times i=2.0\ M\times2 = 4.0\ M$. For $AlCl_3$, effective concentration $=1.5\ M\times i = 1.5\ M\times4=6.0\ M$.
Step3: Analyze freezing - point depression
The greater the effective concentration of solute particles, the lower the freezing point. Since $6.0\ M>4.0\ M$, $1.5\ M\ AlCl_3$ has a lower freezing point.
Step4: Analyze boiling - point elevation
The greater the effective concentration of solute particles, the higher the boiling point. Since $6.0\ M > 4.0\ M$, $1.5\ M\ AlCl_3$ has a higher boiling point.
Answer:
- B. $1.5\ M\ AlCl_3$
- B. $1.5\ M\ AlCl_3$